The chemicals required in a water treatment plant may include chlorine, caustic, phosphates, lime/soda ash, fluoride, coagulants, and several others. Of these, the coagulants, such as alum, ferric chloride, or ferric sulfate, typically account for the largest portion of spending among these chemicals. Additionally, the used coagulants from a water treatment plant add to the amount of residuals that must be disposed of, which adds more cost to the total waste disposal cost of the plant. Coagulation is a process that provides for the removal of solids from the water, especially colloidal or very small particles. Additionally, organic matter and dissolved heavy metals are also removed by coagulation. Generally, coagulant chemicals are used to neutralize the electrical charges of the fine particles in the water, allowing the particles to move closer together and form larger clumps, which are then removed in the treatment process. When coagulant recovery is attempted in a drinking water treatment plant, acid is needed, which in addition to dissolving the precipitated coagulants can also solubilize the removed organic matter and heavy metals. The acid also counteracts the cost savings of recovering the coagulant. Because of these potential issues, coagulant recovery is rarely performed in drinking water treatment plants in the United States.